JP5886529B2 - Mullite sintered body, multilayer wiring board using the same, and probe card - Google Patents

Description

  The present invention relates to a mullite sintered body having low thermal expansion and low dielectric loss, a multilayer wiring board and a probe card using the same.

Conventionally, a semiconductor element storage package is known as a casing for environmentally protecting semiconductor elements such as LSIs embedded in electronic devices, improving heat dissipation of the semiconductor elements, and stabilizing operating characteristics. A multilayer wiring board is used. In recent years, as semiconductor devices have been increased in speed and density, a mounting method called flip-chip mounting in which semiconductor devices are directly mounted on a multilayer wiring board has been adopted. As the size of the semiconductor device increases, the stress generated by the temperature change during mounting between the multilayer wiring board increases. Such stress is caused by the difference between the thermal expansion coefficient of the multilayer wiring board and the thermal expansion coefficient of silicon (Si), which is the material of the semiconductor element (silicon: 2.5 to 3.5 × 10 ⁻⁶ / ° C.). It is. For this reason, attempts have been made to adopt a mullite sintered body having a small difference in thermal expansion coefficient from silicon as a material for the insulating layer (see, for example, Patent Document 1).

JP 10-245263 A

  However, since the mullite sintered body described in Patent Document 1 has a large dielectric loss tangent, there is a problem that the transmission characteristic of an electric signal propagating through the internal wiring layer of the multilayer wiring board is deteriorated when used as an insulating layer. there were.

  Accordingly, an object of the present invention is to provide a mullite sintered body having a small thermal expansion coefficient and a small dielectric loss tangent, a multilayer wiring board and a probe card using the mullite sintered body as an insulating layer.

Mullite sintered body of the present invention, as the main peak obtained by X-ray diffraction, a mullite crystal phase as a main crystal phase, the grain boundary, composition formula _{Mg x Al y Ti z O w} (x = 0.2~ 0.5, y = 1.2 to 1.7, z = 1.1 to 1.5, and w = 4.5 to 5.5) and the magnesium magnesium titanate crystal phase and the manganese titanate crystal phase It is characterized by containing only .

Further, in the mullite sintered body, the aluminum titanate with respect to a crystal phase obtained by combining the mullite crystal phase, the aluminum magnesium titanate crystal phase and the manganese titanate crystal phase, which is obtained from a Rietveld analysis by X- ray diffraction. the ratio of the magnesium crystal phase 1.1-1.5% by mass Rukoto is desirable.

In the mullite sintered body, the ratio of the manganese titanate crystal phase to the crystal phase obtained by combining the mullite crystal phase, the aluminum magnesium titanate crystal phase, and the manganese titanate crystal phase is 1.1 to 1. 5% by mass Rukoto is desirable.

  The multilayer wiring board of the present invention is a multilayer wiring board comprising an insulating substrate formed by laminating a plurality of insulating layers, and an internal wiring layer formed inside the insulating substrate, the insulating layer being the above-mentioned It is characterized by comprising a mullite sintered body.

The probe card of the present invention is characterized in that a surface wiring layer is provided on the surface of the multilayer wiring board, and a measurement terminal for measuring electrical characteristics of a semiconductor element is connected to the surface wiring layer. To do.

  According to the present invention, it is possible to obtain a mullite sintered body having a small thermal expansion coefficient and a small dielectric loss tangent, and a multilayer wiring board and a probe card using this as an insulating layer.

It is a schematic sectional drawing of one Embodiment of the multilayer wiring board of this invention. It is a schematic sectional drawing of one Embodiment of the probe card of this invention.

The mullite sintered body of the present embodiment is characterized in that mullite is used as a main crystal phase and contains aluminum magnesium titanate, so that the thermal expansion coefficient is 4.8 × 10 ⁻⁶ / A mullite sintered body having a small temperature of ℃ or less and a small dielectric loss tangent can be obtained. This is because a crystalline phase of aluminum magnesium titanate (70 × 10 ⁻⁴ or less (1 MHz)) having a low dielectric loss tangent as a simple substance is formed in the mullite sintered body.

Here, mullite as a main crystal phase means a composition obtained when a Rietveld analysis by X-ray diffraction is performed on a mullite sintered body, and contains mullite in an amount of 70% by mass or more. , in the chemical formula represented as _{aAl 2 O 3 · bSiO 2,} a = 1.9~3.2, it is desirable to have a composition of b = 0.9-2.1.

As the magnesium aluminum _titanate, in the chemical formula represented by _{Mg x Al y Ti z O W} , X = 0.2~0.5, y = 1.2~1.7, Z = 1.1~ Those having a composition of 1.5 and w = 4.5 to 5.5 are preferred.

  The crystal phase of mullite constituting the mullite-based sintered body of the present embodiment exists in the sintered body as particulate or columnar crystals. Mullite has improved thermal conductivity as the crystal grain size increases, and strength increases as the crystal grain size decreases. Therefore, it is possible to achieve both high thermal conductivity and high strength, and to form the maximum in a mullite sintered body. For the reason that the pore diameter is 20 μm or less, the average particle size of mullite is desirably 1.0 to 5.0 μm, particularly 1.7 to 2.5 μm.

  Here, the average particle size of mullite is determined by polishing a portion of the mullite-based sintered body cut out from the wiring board, taking a photograph of the internal structure of the etched sample using a scanning electron microscope, and about 50 on the photograph. Draw a circle to enter, select mullite crystal particles that fall within and around the circle, then image the outline of each crystal particle to determine the area of each crystal particle, and replace it with a circle with the same area The diameter is calculated from the average value.

  The maximum pore diameter of the mullite sintered body is measured by, for example, a scanning electron microscope or an image analysis apparatus after polishing and etching the portion of the mullite sintered body cut out from the wiring board. In this case, first, a 300 μm square region at the center of the polished surface of the prepared sample was observed at a magnification of 100 to 300 times to measure the pore diameter existing on the polished surface, and the maximum pore diameter was determined from the measured pores. Ask for.

In addition, in the mullite sintered body of the present embodiment, it is desirable that aluminum magnesium titanate is contained in an amount of 1.0 to 1.5% by mass in a composition obtained from a Rietveld analysis by X-ray diffraction. By including aluminum magnesium titanate in such a range in the mullite sintered body, the thermal expansion coefficient of the mullite sintered body from room temperature to 300 ° C. is 3.7 to 4.1 × 10 ⁻⁶ / ° C., It becomes possible to make the dielectric loss tangent 300 × 10 ⁻⁴ or less.

  Furthermore, it is desirable that the mullite sintered body of the present embodiment has a composition obtained from Rietveld analysis by X-ray diffraction and further contains 1.1 to 1.5 mass% of manganese titanate. Thereby, the mechanical strength (three-point bending strength) of the mullite sintered body can be increased to 335 MPa or more, and the chemical resistance can be improved. In this case, when manganese titanate is present at the grain boundary, the glass phase present at the grain boundary can be reduced, so that the chemical resistance of the mullite sintered body can be improved. Further, since the grain boundary becomes crystalline, the bond between mullite crystals is strengthened, and thereby the mechanical strength of the mullite sintered body can be increased. In this embodiment, the chemical resistance is high because, for example, even if the mullite sintered body is immersed in an aqueous solution in which about 40% by mass of potassium hydroxide is dissolved, the mullite sintered body The elution amount of the contained glass component is a level of 0.12% or less in terms of weight change rate.

  FIG. 1 is a schematic cross-sectional view of an embodiment of a multilayer wiring board of the present invention. A multilayer wiring board 1 shown in FIG. 1 includes an insulating base 11 and an internal wiring layer 12 formed inside the insulating base 11, and at least the internal wiring layers 12 are electrically connected to each other inside the insulating base 11. And via-hole conductors 14 connected to each other.

The insulating base 11 is formed by laminating a plurality of insulating layers 11a, 11b, 11c, and 11d (hereinafter referred to as 11a to d), and each of the insulating layers 11a to 11d is formed of the above-described mullite sintered body. ing. When the insulating base 11 is the mullite sintered body described above, the thermal expansion coefficient (room temperature to 300 ° C.) of the insulating base 11 can be set to a range of 4.8 × 10 ⁻⁶ / ° C. or less. The multilayer wiring board 1 can reduce stress caused by a temperature change during mounting with a semiconductor element such as an LSI. As a result, the multilayer wiring board 1 with high connection reliability can be obtained even when the semiconductor element is flip-chip mounted. In addition, since the dielectric loss tangent can be reduced in the multilayer wiring board 1 of the present embodiment, the transmission characteristics of the multilayer wiring board 1 can be improved.

  In this case, in terms that the thermal expansion coefficient and dielectric loss tangent of the insulating substrate 11 can be further reduced, the mullite sintered body forming the insulating layers 11a to 11d has a composition obtained from a Rietveld analysis by X-ray diffraction, and aluminum titanate. It is desirable to contain 1.0-1.5 mass% of magnesium.

  Further, in the multilayer wiring board 1 of the present embodiment, the mullite sintered body forming the insulating layers 11a to 11d has a composition obtained from Rietveld analysis by X-ray diffraction, and further contains manganese titanate of 1.1 to It is desirable to contain 1.5% by mass. In this case, the mechanical strength of the insulating substrate 11 can be increased and the chemical resistance can be increased.

  Usually, a sintering temperature of 1450 ° C. or higher is required to sinter a molded body material mainly composed of mullite. However, as the insulating layers 11a to 11d constituting the multilayer wiring board 1 of the present embodiment, When formed with a mullite sintered body containing manganese, titanium and magnesium, a dense mullite sintered body can be obtained at a firing temperature of 1380 ° C. to 1420 ° C. as described later. It becomes possible to give sufficient mechanical strength.

In addition, in a mullite sintered body in which only manganese titanate is present at the grain boundary of the mullite crystal phase, the dielectric loss is remarkably large. For example, an electric signal evaluated using an internal wiring layer for signals is used. Although the transmission characteristics are likely to be delayed, in the multilayer wiring board 1 of the present embodiment, crystals of aluminum magnesium titanate together with manganese titanate are present at the grain boundaries of the mullite crystal phase. The chemical resistance can be enhanced, and an increase in the dielectric loss tangent due to the presence of only manganese titanate at the grain boundary can be suppressed, whereby the electric signal transmission characteristics of the internal wiring layer 12 can be enhanced.

  In the multilayer wiring board 1 of the present embodiment, the internal wiring layer 12 and the via-hole conductor 14 are preferably composed mainly of any one of tungsten, molybdenum, and copper. In particular, it is desirable to contain copper in that the conductor resistance of the internal wiring layer 12 and the via-hole conductor 14 can be reduced to reduce the transmission loss caused by the conductor. For example, when the mullite sintered body containing aluminum magnesium titanate and manganese titanate is used as the insulating layers 11a to 11d, at least one of 40 to 60% by volume of copper and Mo and W as the internal wiring layer 12 is used. It is preferable to use a composite conductor having a composition of 40 to 60% by volume. If this composite conductor is used, the sintering temperature of the insulating layers 11a to 11d can be approached. As a result, the insulating layers 11a to 11d can be densified, and the internal wiring layer 12 can be formed with a small size variation and a dense internal wiring layer 12. In this way, a multilayer wiring board having the low-resistance internal wiring layer 12 and the via-hole conductor 14, low thermal expansion, small dielectric loss tangent, and excellent chemical resistance can be obtained.

  FIG. 2 is a schematic sectional view of an embodiment of the probe card of the present invention. In the probe card 2 of this embodiment, a surface wiring layer 21 is provided on the surface of the multilayer wiring board 1 of FIG. 1, and a measurement terminal 23 for measuring the electrical characteristics of the semiconductor element is connected to the surface wiring layer 21. It has been done. In the probe card 2 of the present embodiment, the connection terminal 31 is formed on the surface opposite to the surface on which the measurement terminal 23 is provided, and the external circuit board 33 is joined via the connection terminal 31. Yes. Further, the external circuit board 33 is connected to a tester 34, and many external circuit boards 33 are formed on the semiconductor wafer 37 by bringing the measurement terminals 23 of the probe card 2 into contact with the upper surface of the semiconductor wafer 37 placed on the stage 35. The electrical characteristics of the semiconductor element can be measured. The probe card 2 can be driven up and down by an elevating device 39, and the measurement terminal 23 of the probe card 2 is brought into contact with or separated from the upper surface of the semiconductor wafer 37.

  When the multilayer wiring board 1 of the present embodiment is applied to the probe card 2, the thermal expansion coefficient of the probe card 2 is reduced because the insulating base 11 constituting the multilayer wiring board 1 is composed of the mullite sintered body described above. be able to. Thereby, for example, in the thermal load test in the case of conducting an electrical inspection of the semiconductor wafer 37, the measurement terminal 23 formed on the surface of the multilayer wiring board 1 constituting the probe card 2 and the measurement formed on the surface of the semiconductor wafer 37 There is almost no misalignment with the pad, and it can be suitably used in the inspection of electrical characteristics.

  Further, in the probe card 2 of the present embodiment, since the mullite sintered body having a small dielectric loss tangent is used as the insulating substrate 11 constituting the multilayer wiring board 1, it has an electric circuit having excellent transmission characteristics. Can do.

  In this case, also in the probe card 2, the insulating substrate 11 of the multilayer wiring board 1 constituting the probe card 2 contains 1.0 to 1.5% by mass of aluminum magnesium titanate with a composition obtained from a Rietveld analysis by X-ray diffraction. It is desirable to contain 1.1 to 1.5% by mass of manganese titanate.

Moreover, when the above-mentioned mullite sintered body containing aluminum magnesium titanate and manganese titanate is applied as the insulating base 11 of the multilayer wiring board 1 constituting the probe card 2 of the present embodiment, the multilayer wiring board 1 is Since the coefficient of thermal expansion is small and the mechanical strength (three-point bending strength) is high, there is no damage even when tightening bolts when assembling the multilayer wiring board 1 to the probe card 2, and the probe card 2 It is possible to reduce the deflection when the size is increased. As a result, the positions of the tips of all the measurement terminal probe pins in the probe card 2 can be brought close to the same height, and the accuracy of the inspection of the electrical characteristics can be increased.

  Further, on the main surface of the insulating substrate 11 constituting the multilayer wiring substrate 1 shown in FIG. 1, a land pattern (not shown) that is originally connected to the via-hole conductor 14 instead of the surface wiring layer 21 immediately after firing. Is formed. This land pattern is provided for performing a short or open inspection of the electrical connection between the internal wiring layer 12 and the via-hole conductor 14 of the multilayer wiring board 1 for the probe card 2 after firing. Then, after performing a short or open inspection of the electrical connection between the internal wiring layer 12 and the via-hole conductor 14 of the multilayer wiring board 1, the land pattern is removed by polishing to expose the via-hole conductor 14, and then a sputtering method. Alternatively, the surface wiring layer 21 is formed by a thin film method such as an evaporation method, and further, measurement terminals (probe pins) 23 are formed on the surface of the surface wiring layer 21 to form the probe card 2 shown in FIG.

  Next, a method for manufacturing the mullite sintered body of this embodiment and the multilayer wiring board 1 and the probe card 2 using the same will be described.

First, mullite (3Al ₂ O ₃ .2SiO ₂ ) powder having a purity of 99% or more and an average particle size of 0.5 to 2.5 μm is prepared. By using a mullite powder having an average particle size of 0.5 μm or more, the formability of the sheet for forming the insulating layers 11 a to 11 d of the multilayer wiring board 1 can be improved, and the mullite powder is 2.5 μm or less. By using this, densification can be promoted even by firing at a temperature of 1420 ° C. or lower.

  Next, a small amount of each of magnesium oxide powder and anatase-type titanium dioxide powder is added to the mullite powder to prepare a mixed powder. By using such a mixed powder, a crystalline phase of aluminum magnesium titanate can be formed in the mullite sintered body, thereby obtaining a mullite sintered body having a low thermal expansion coefficient and a low dielectric loss tangent. be able to. Here, anatase-type titanium dioxide powder means that when the titanium dioxide powder is identified by X-ray diffraction, the diffraction intensity of the main peak of rutile-type titanium dioxide is the diffraction intensity of the main peak of anatase-type titanium dioxide. In contrast, it is 10% or less.

  Further, when using a mixed powder obtained by adding 1-2% by mass of magnesium oxide powder and 2-6% by mass of anatase-type titanium dioxide powder to 100% by mass of mullite powder, 1.0 mg of aluminum magnesium titanate is used. A mullite sintered body containing ˜1.5 mass% can be obtained.

Furthermore, with respect to 100% by mass of mullite powder, magnesium oxide powder is 1 to 2% by mass, anatase type titanium dioxide powder is 2 to 6% by mass, and manganese oxide (Mn ₂ O ₃ ) powder is 1 to 3% by mass. %, And when sintered at a maximum temperature of 1380 to 1420 ° C., 1.0 to 1.5 mass% of aluminum magnesium titanate is contained, and manganese titanate is 1.1 to A mullite sintered body containing 1.5% by mass can be obtained. In this case, manganese oxide powder used as an additive has an average particle size of 0.5 to 3 μm, anatase-type titanium dioxide powder has an average particle size of 0.5 to 2 μm, and magnesium oxide powder has an average particle size of 0.5 to 3 μm. These manganese oxide powders, titanium dioxide powders, and magnesium oxide powders preferably have a purity of 99% by mass or more. Thereby, the diffusion of Mn, Ti and Mg can be improved, and a dense sintered body can be obtained. When rutile titanium dioxide powder is used as the titanium dioxide powder, it becomes difficult to form a crystalline phase of aluminum magnesium titanate in the mullite sintered body, and a mullite sintered body having a small dielectric loss tangent is required. Can't get.

  Next, an organic binder and a solvent are added to the mixed powder to prepare granules or slurry, and then the green powder or powder is formed by a pressing method, a doctor blade method, a rolling method, an injection method, or the like. Create a body. In addition, although the thickness of a green sheet or a molded object can be 50-300 micrometers, for example, it is not specifically limited.

  Here, when the multilayer wiring board 1 is manufactured, a through hole having a diameter of 50 to 250 μm is appropriately formed in the green sheet by a micro drill, a laser, or the like.

  The green sheet thus formed with the through holes is filled with a conductive paste containing at least one metal powder of copper powder, tungsten powder and molybdenum powder, for example, screen printing, gravure printing, etc. A wiring pattern is formed by printing and coating by a method. As the conductor paste, it is desirable to use tungsten powder, molybdenum powder, or a mixture of these powders with copper powder in that the low-resistance internal wiring layer 12 and the via-hole conductor 14 can be formed.

  Thereafter, the green sheet on which the conductive paste is printed and applied is aligned and laminated and pressed to produce a laminate. Then, the obtained laminate or molded body is fired in a non-oxidizing atmosphere (a nitrogen atmosphere or a mixed atmosphere of nitrogen and hydrogen).

  The mullite sintered body produced by the method described above has low thermal expansion and low dielectric loss, and can be suitably used as, for example, the insulating substrate 11 of the multilayer wiring board and the probe card 2.

Mn ₂ O ₃ powder having a purity of 99% and an average particle diameter of 1.5 μm, with respect to 100 parts by mass of mullite powder (3Al ₂ O ₃ .2SiO ₂ ) having a purity of 99% and an average particle diameter of 2.1 μm, TiO ₂ powder (anatase type and rutile type) having a purity of 99% and an average particle diameter of 1.0 μm, and a MgO powder having a purity of 99% and an average particle diameter of 0.7 μm as shown in Tables 1 and 2 In addition, after preparing a slurry by further mixing an acrylic binder as an organic resin for molding (organic binder) and toluene as an organic solvent, it is molded into a sheet having a thickness of 200 μm by the doctor blade method, A green sheet was produced.

  15 layers of the obtained green sheets were laminated, degreased in a nitrogen-hydrogen mixed atmosphere at a temperature of room temperature to 600 ° C., and then for one hour at the maximum temperature shown in Tables 1 and 2 in the same firing atmosphere. Firing was performed under the condition of holding, and a mullite sintered body was obtained.

Regarding the crystal phase present in the mullite sintered body and the ratio thereof, first, the mullite sintered body is pulverized, the main peak position obtained by X-ray diffraction is compared with JCPDS, mullite, aluminum magnesium titanate ( The crystal phases of Mg _0.3 Al _1.4 Ti _1.3 O ₅ ) and manganese titanate (MnTiO ₃ ) were identified. As a result, it was confirmed that mullite was present as the main crystal phase. Further, as other crystal phases, the presence or absence of crystal phases of aluminum magnesium titanate and manganese titanate, and the identified crystal phases of aluminum magnesium titanate (Mg _0.3 Al _1.4 Ti _1.3 O ₅ ) and For manganese titanate (MnTiO ₃ ), the crystal phase ratio was determined by Rietveld analysis.

Further, as an indicator of chemical resistance, the initial mass of the mullite sintered body and the mass of the mullite sintered body after being immersed in a 40% by weight aqueous solution of potassium hydroxide at 100 ° C. for 5 hours were measured, and the weight decreased. Ratio (“initial mass of mullite sintered body” − “mass of mullite sintered body after being immersed in 40% by weight aqueous solution of potassium hydroxide at 100 ° C. for 5 hours”) / “initial stage of mullite sintered body” The “mass” × 100 [%] was calculated. Here, the chemical resistance was judged as a non-defective product (◯) when the weight change rate was 0.12% by mass or less.

  Further, a mullite sintered body prepared by laminating 30 layers of the obtained green sheets under the same degreasing and firing conditions as described above was used to obtain a width of 3 mm and a thickness using a plane polishing machine. The sample was processed into a sample having a shape of 2 mm and a length of 1 mm to prepare a sample for TMA analysis (thermomechanical analysis), and the thermal expansion coefficient at room temperature to 300 ° C. was measured.

  Further, based on the bending strength test method defined in JIS R1601, three-point bending strength was measured. Here, the sample used for the measurement had a length of about 20 mm, a width of about 2 mm, and a thickness of about 1.5 mm.

  The evaluation of X-ray diffraction, chemical resistance, and thermal expansion coefficient was obtained from an average value with three samples. Further, the evaluation of the three-point bending strength was obtained from an average value with 10 samples.

  In addition, a conductor paste prepared by making Cu powder and W powder 45% by volume of Cu powder and 55% by volume of W powder is printed on the surface of each green sheet. A green sheet in which a via conductor was formed by forming a wiring pattern and filling the through hole with a conductive paste of Mo was produced.

  At this time, an evaluation pattern having a line width of 100 μm and a length of 20 mm is formed on a part of the internal wiring pattern for resistance measurement, and the internal wiring pattern is connected to the via conductor. A land pattern was formed at the end of each for connection with a via conductor.

  The ceramic green sheets thus produced were aligned and laminated and pressed to produce a laminate. In the laminate produced here, a ceramic green sheet provided with pads for contacting measurement terminals for resistance measurement is arranged on the uppermost layer, and an internal wiring pattern and land for resistance measurement are arranged on the second layer. A ceramic green sheet with a pattern printed on it is placed, and the through hole (filled with Mo conductor paste) provided in the uppermost layer is electrically connected to the land printed with the second layer. In addition, the ceramic green sheets of all 30 layers are laminated.

  Next, the laminate was degreased in a nitrogen-hydrogen mixed atmosphere at a temperature of room temperature to 600 ° C., and then continuously heated to the maximum temperature in the same firing atmosphere as in the case of producing the mullite sintered body described above. Was held at 1400 ° C. or 1500 ° C. for 1 hour and baked to produce a multilayer wiring board for a probe card. The substrate size was 340 mm × 340 mm and the thickness was 5 mm.

  Next, after polishing the surface of the produced probe card multilayer wiring board and removing the land pattern, the surface of the probe card ceramic wiring board is Ti and Cu having a thickness of about 2 μm by sputtering. The conductive thin films were sequentially formed.

  Next, a conductive thin film of Ti and Cu is patterned by photolithography, and an electrolytic plating film of Ni and Au is sequentially formed on the surface of Cu, and the via hole conductor on the surface of the multilayer wiring board for the probe card is formed. A surface wiring layer for a probe card was formed.

  Next, a Si measurement terminal (probe pin) was joined to the surface of the surface wiring layer formed on the multilayer wiring board to produce a probe card.

  The insulating base portion was cut out from the multilayer wiring board of the produced probe card, and the dielectric loss tangent (tan δ) at a frequency of 1 MHz was measured using a bridge circuit method to evaluate the dielectric loss tangent of the insulating base.

The content of manganese (Mn), titanium (Ti), and magnesium (Mg) contained in the insulating substrate is determined by dissolving the insulating substrate cut out from the multilayer wiring board of the probe card once in acid, Qualitative analysis of the elements contained in the dielectric porcelain was carried out by absorption analysis, and then the standard solution was diluted for each of the specified elements and quantified by ICP emission spectroscopic analysis. In this case, the contents of aluminum (Al), silicon (Si), manganese (Mn), titanium (Ti) and magnesium (Mg) contained in the insulating substrate are determined by ICP analysis, and aluminum ( seeking mullite _{(3Al 2 O 3 · 2SiO 2} ) the amount of al) and silicon (Si), further Mn relative amounts of mullite, the amount of Ti and Mg in the amounts shown in Table 1 and Table 2 was determined in terms of oxide Each was consistent.

  Further, the composition of Cu and W of the internal wiring layer is a conductor material obtained by cutting out a portion where the internal wiring layer is formed from the probe card wiring board and dissolving the solution in an acid using ICP analysis. The contents of Cu and W were determined by mass. Next, the amounts of Cu and W obtained as masses were divided by the respective densities to determine the respective volumes, and then the ratio of Cu and W when the total volume of Cu and W was taken as 100% was determined. . In addition, it was confirmed that the internal wiring layer formed on the produced probe card wiring board was 45% by volume of Cu and 55% by volume of W.

As is clear from the results of Table 1, all of the samples of the present invention (sample Nos. 1-3, 7-10, 12-14, 18-21, 23, and 24) were titanium in the mullite sintered body. A crystal phase of aluminum magnesium oxide was present, the thermal expansion coefficient from room temperature to 300 ° C. was 4.8 × 10 ⁻⁶ / ° C. or less, and the dielectric loss tangent was 310 × 10 ⁻⁴ or less.

Moreover, the sample (sample No. 2, 3, 7-9, 13, 14, 18 which contains 1.0-1.5 mass% of aluminum magnesium titanate by the composition calculated | required from the Rietveld analysis by X-ray diffraction. -20, 23, and 24), the thermal expansion coefficient of the mullite sintered body from room temperature to 300 ° C. was 3.7 to 4.1 × 10 ⁻⁶ / ° C., and the dielectric loss tangent was 300 × 10 ⁻⁴ or less. .

  Furthermore, a sample containing 1.0 to 1.5% by mass of aluminum magnesium titanate and 1.1 to 1.5% by mass of manganese titanate with a composition obtained from a Rietveld analysis by X-ray diffraction. In (Sample Nos. 13, 14, and 18 to 20), the three-point bending strength was 335 MPa or more and the chemical resistance was good.

  These samples of the present invention are sample Nos. When a multilayer wiring board produced using a mullite sintered body of 1 to 3, 7 to 10, 12 to 14, 18 to 21, 23 and 24 is applied to a probe card, There was no misalignment between the measurement terminal provided on the probe card ceramic wiring board and the measurement pad formed on the surface of the Si wafer, and it could be suitably used for inspection of electrical characteristics. Also, when assembled as a probe card, there was no damage due to bolt tightening. In addition, since the dielectric loss tangent is low, there is no delay in the evaluation of the electric signal transmission characteristics using the signal internal wiring layer, and the dielectric loss tangent can be suitably used.

On the other hand, the samples (sample Nos. 4 to 6, 11, 15 to 17, and 22) do not contain aluminum titanate, and therefore the dielectric loss tangent of the mullite sintered body is all increased by 310 × 10 ⁻⁴ . It was higher.

1: Multilayer wiring board 11: Insulating bases 11a, 11b, 11c, 11d: Insulating layer 12: Internal wiring layer 14: Via hole conductor 2: Probe card 21: Surface wiring layer 23: Measurement terminal

Claims (5)

As the main peak obtained by X-ray diffraction, a mullite crystal phase as a main crystal phase, the grain boundary, composition formula _{Mg x Al y Ti z O w} (x = 0.2~0.5, y = 1.2~ 1.7, comprising only an aluminum magnesium titanate crystal phase and a manganese titanate crystal phase represented by z = 1.1 to 1.5 and w = 4.5 to 5.5) A mullite sintered body.   The ratio of the aluminum magnesium titanate crystal phase to the crystal phase of the mullite crystal phase, the aluminum magnesium titanate crystal phase, and the manganese titanate crystal phase determined from a Rietveld analysis by X-ray diffraction is 1.1 to It is 1.5 mass%, The mullite sintered body of Claim 1 characterized by the above-mentioned.   A ratio of the manganese titanate crystal phase to the crystal phase obtained by combining the mullite crystal phase, the aluminum magnesium titanate crystal phase, and the manganese titanate crystal phase is 1.1 to 1.5% by mass. The mullite sintered body according to claim 2.   A multilayer wiring board comprising: an insulating substrate formed by laminating a plurality of insulating layers; and an internal wiring layer formed inside the insulating substrate, wherein the insulating layer is any one of claims 1 to 3. A multilayer wiring board comprising the mullite sintered body described in 1.   5. A probe card, wherein a surface wiring layer is provided on a surface of the multilayer wiring board according to claim 4, and a measurement terminal for measuring electrical characteristics of a semiconductor element is connected to the surface wiring layer. .

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